Distance number on log tracked entry progress screen should be monospace

[whyceewhite]

On the log tracked entry progress scene, the distance value lable is centered. When the distance number is changing, the text appears to jump because the numbers are not monospaced. Figure out a way to make the preferred font monospace so that it appears still.

[whyceewhite]

This Using fonts with Text Kit reference provided information on monospacing the font for a numerical element.

Here's an example of how I did it:

        let font = UIFont.preferredFontForTextStyle(UIFontTextStyleTitle1)
        let fontDescriptor = font.fontDescriptor()
        var fontAttributes = [String : AnyObject]()
        fontAttributes[UIFontDescriptorFeatureSettingsAttribute] = [
            [
                UIFontFeatureTypeIdentifierKey : kNumberSpacingType,
                UIFontFeatureSelectorIdentifierKey : kMonospacedNumbersSelector
            ]
        ]
        let propDescriptor = fontDescriptor.fontDescriptorByAddingAttributes(fontAttributes)
        return UIFont(descriptor: propDescriptor, size: 0)